Field of the Invention
The present invention relates to a wireless communication, and more particularly, to a method for performing channel sounding in a wireless LAN system and an apparatus for supporting the same.
Related Art
In recent years, with development of information communication technology, various wireless communication technologies have been developed. Among them, a wireless local area network (WLAN) is technology that can wirelessly access the Internet in a home or an enterprise, or a specific service providing area by using a portable terminal a personal digital assistant (PDA), a laptop computer, a portable multimedia player (PMP), or the like based on radio frequency technology.
As the existing wireless LAN system that supports high throughput (HT) and very high throughput, a wireless LAN system that can be operated in a band of 1 GHz or less unlike using a bandwidth of 20/40/80/160/80+80 MHz of a 2 GHz and/or 5 GHz band. When the wireless LAN system is operated in the band of 1 GHz or less, a channel which is considerably narrower than the existing wireless LAN system is used. As a result, service coverage can be extended as compared with service coverage of the existing wireless LAN system.
Meanwhile, when a frequency band based on operation of the wireless LAN system is changed, a format of a physical layer data unit suitable for a changed characteristic of a physical layer needs to be proposed. Further, a channel sounding method that can support channel state information in a changed channel band to be fed back is requested.